#include <iostream>

using namespace std;

void PrintArray(int* arr) {
    int len = sizeof(arr) / sizeof(int);
    cout << len << endl;
    cout << sizeof(arr) << sizeof(int) << endl;
    cout << "[";
    for (int i = 0; i < len; i++) {
        cout << arr[i] << " ";
    }
    cout << "]" << endl;
}

int main() {
    int* arr = (int*)malloc(20 * sizeof(int));

    // 这里又发现测不准了
    int len = sizeof(arr) / sizeof(int);
    cout << len << endl;

    PrintArray(arr);
    return 0;
}
